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GPT 5.1 Codex Mini

GPT 5.1 Codex Mini is the lightweight, fast variant in the GPT-5.1 codex family, optimized for routine coding tasks like bug fixes, feature scaffolding, and test generation at a cost that scales to high-frequency CI and development workflows.

ReasoningFile InputVision (Image)Tool UseImplicit Caching
index.ts
import { streamText } from 'ai'
const result = streamText({
model: 'openai/gpt-5.1-codex-mini',
prompt: 'Why is the sky blue?'
})